How to Write Alt Text for Images

What the alt text check tests

SiteCurl scans every <img> tag on your page and checks whether it has an alt attribute. Images without alt text are flagged. Images with generic alt text like “image” or the filename (“IMG_4532.jpg”) are flagged as warnings.

Why it matters

Screen readers announce images by reading their alt text aloud. Without alt text, a blind visitor hears “image” or nothing at all. They have no idea what the image shows or whether it matters.

Alt text also serves as a fallback when images fail to load (slow connections, broken URLs, email clients that block images). And search engines use alt text to understand image content, which affects image search rankings and overall page relevance.

How to fix it

Writing good alt text

Describe what the image shows, not what it is. Be specific and concise.

Good examples:

• alt="Team members gathered around a whiteboard during a planning session"
• alt="Bar chart showing 40% increase in organic traffic from January to March"
• alt="Red leather wallet with brass clasp, front view"

Bad examples:

• alt="image" (tells the user nothing)
• alt="IMG_4532.jpg" (filename, not a description)
• alt="photo of our team" (too vague)
• alt="" on a meaningful image (hides it from screen readers)

Keep it under 125 characters

Screen readers handle long alt text awkwardly. If you need more context, describe the image briefly in alt text and provide detail in the surrounding text or a caption.

When to use empty alt text

Decorative images that add visual interest but convey no information should have alt="" (empty alt, not missing alt). This tells screen readers to skip the image entirely.

Examples of decorative images: background patterns, divider lines, icons that duplicate adjacent text labels.

<!-- Decorative: skip it -->
<img src="divider.svg" alt="">

<!-- Meaningful: describe it -->
<img src="product.jpg" alt="Blue running shoes, side view">

CMS tips

In WordPress, the alt text field appears in the media library when you select an image. In Squarespace, click the image block and look for the “Alt text” field. In Shopify, edit alt text in the product image settings.

How to verify the fix

Right-click an image, choose Inspect, and confirm the alt attribute is present and descriptive. Run a SiteCurl scan to check all images across your site. The accessibility section lists every image with missing or weak alt text.

Related checks

Alt text is one piece of accessibility. Also check form labels and heading hierarchy for a more complete picture.

Start a free trial to find every image missing alt text.